1. Field of the Invention
The present invention concerns an antenna element for magnetic resonance applications of the type having a sub-section extending along a section axis. The present invention also concerns an antenna arrangement for magnetic resonance applications with a number of such antenna elements parallel to one another.
2. Description of the Prior Art
Antenna elements for magnetic resonance applications and corresponding antenna arrangements are generally known. In particular, the antenna elements can be fashioned as antenna rods of a birdcage resonator or as axially proceeding parts of a saddle coil.
In magnetic resonance applications, radio-frequency coils (resonators) are used for the excitation and the reception of radio-frequency alternating magnetic fields. In addition to a homogenous static magnetic field, an optimally homogenous radio-frequency field is also required for imaging. For example, cylindrical radio-frequency coils (birdcage resonators, saddle coils) exhibit a very homogenous radio-frequency profile.
Non-uniform loading of the radio-frequency coils, electrical shielding and dielectric resonance in the examination subject can lead to different excitations of the magnetic resonances. Such different excitations lead to effects known as shadowing effects (shadows) in the generated images.
For high-resolution exposures, it is therefore not sufficient to keep the current distribution on the antenna elements of the radio-frequency coil (or the antenna arrangement) constant. Rather, it can be necessary to individually adjust the current distribution, in particular dependent on the examination subject.